Antifungal properties of a new series of terpolymer resins, prepared by the polycondensation reaction of benzyl-2,4-dihydroxyphenyl keton (BPK), formaldehyde/furfural and 4-oxoacids using acid catalyst, was studied against two pathogenic fungi such as Fusarium oxysporum and Dreschlera halodes. All the newly prepared resins were characterised by spectral data, physicochemical and thermal analyses. The copolymer resins (BPK-formaldehyde and BPK-furfural) were devoid of antifungal activity, while all the terpolymer resins were toxic at one or other concentrations. Within the terpolymer resins, furfural based resins were highly toxic against both the fungi and caused total germination inhibition at 640 ppm concentration. These terpolymer resins were equipotent with that of standard Clotrimazole. Both the pathogens were equivally sensitive to the terpolymer resins.